// 基础类型，boolean, number, string, void, undefined, symbok, null
let count: number;
count = 123;

// 对象类型，{}, Class, function, []
const func = (str: string): number => {
  return parseInt(str, 10);
};

const func1: (str: string) => number = (str) => {
  return parseInt(str, 10);
};

const date = new Date();

// 其它的 case
const rawData = '{"name":"dell"}';
const newData = JSON.parse(rawData);

let temp: number | string = 123;
temp = "456";
